The scientists in Earth on Edge say that humans are failing to wisely
manage the ecosystems on which our lives depend. And, as the marine
ecologist in the program, Carl Safina, reminds us, "Our everyday choices
 those we make shopping, eating, building, and commuting 
can make the difference between a passing grade or future failure."

Do you know enough to help guide Earth's ecosystem's to a "passing
grade"? Take our quiz and test your knowledge!

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Question 1

Ecosystems supply us with food, timber, fiber, and places for recreation and spiritual pursuits. They also provide employment. What percent of jobs worldwide are in agriculture, forestry, and fishing?

A. 10%
B. 25%
C. 50%
D. 75%

The correct answer is

Question 2

Ecosystems provide numerous services-air and water purification, climate control, nutrient cycling  that we can't do without. Another important ecosystem service that most people don't think about is pollination. What percent of the world's food crops would not exist without pollinators like bees, bats, and wasps?

A. 20%
B. 50%
C. 75%
D. 90%

The correct answer is

Question 3

The majority of the world's population depends on what kind of fuel as its primary source of energy?

A. Coal
B. Wood
C. Hydropower
D. Oil

The correct answer is

Question 4

Why is New York City spending millions of dollars to purchase and protect lands north and west of the city?

A. City residents want more open space for recreation
B. To ensure the long-term protection of its drinking water supply
C. To provide land for solid waste sites
D. As habitat for endangered species

The correct answer is

Question 5

Why are trees important for urban ecosystems?

A. Trees remove thousands of tons of pollutants from the city air
B. Trees help cool urban areas
C. Trees help reduce urban noise levels
D. All of the above

The correct answer is

Question 6

It takes approximately half a hectare of productive ecosystem to support the consumption levels of the average citizen in a developing country. How does that compare with the ecosystem area needed to support the average US citizen's consumption of goods and services?

A. They are about the same
B. The average American uses twice as much ecosystem area to support his or her consumption as a developing country citizen
C. The average American uses four times as much ecosystem area to support his or her consumption as a developing country citizen
D. The average American uses eight times as much ecosystem area to support his or her consumption as a developing country citizen

The correct answer is

Question 7

The conversion of wildlands to meet human needs  space for farmlands or settlements, for example  has marked the growth of civilization throughout human history. What percent of the world's land has humans converted to agriculture, urban, and suburban areas?

A. 10%
B. 20%
C. 30%
D. 50%

The correct answer is

Question 8

What percent of the world's major marine fish stocks are depleted from overfishing or being fished at their biological limit?

A. 10%
B. 25%
C. 50%
D. 75%

The correct answer is

Question 9

What is the cost of restoring Florida's Everglades, where water quality and quantity and 68 fish and wildlife species are endangered or threatened with extinction?

A. $5 million
B. $4.6 billion
C. $7.8 billion
D. $15 billion

The correct answer is

Question 10

How is most of the water withdrawn from freshwater systems used?

A. For drinking water
B. For irrigation
C. For industrial use
D. None of the above

The correct answer is

Question 11

Cities are expansive consumers of ecosystem goods and services  and prolific generators of ecosystem  damaging wastes. By 2030, what percent of the industrialized world's population will live in urban areas?

A. 40%
B. 50%
C. 80%
D. 90%

The correct answer is

Question 12

How much of the world's wetlands have been lost in the 20th century?

A. 10%
B. 20%
C. 40%
D. 50%

The correct answer is

Question 13

Dams provide hydropower, drinking water, increased agricultural output through irrigation, easier water transport, and flood control. But like most human alterations of ecosystems, dams present tradeoffs. Which of the following are negative tradeoffs that come with damming a river?